CCTV Review Flashcards
Analog cameras cannot be used on a DVR True or False
False
The video standard for Canada is….
a. PAL
b. NTSC
c. NTSC-Canada
d. S-Video
b. NTSC
Which camera is better suited for low light conditions?
a. CCD
b. CMOS
c. DSP
d. FFL
a. CCD
What is the focal length of the human eye?
a. 7mm
b. 10mm
c. 13mm
d. 17mm
d. 17mm
What are the two scanning methods used in the camera and monitor video scanning process?
Raster and Progressive
What are the two types of light sources?
Natural and Artificial
What is the most common type of lens used in video security applications?
FFL
What are the four items required for a simple video system?
lens, monitor, camera, transmission
What is the major reason for video surveillance systems?
Protection of people and property (assets)
What is the cause of video hum?
grounding differences
What is the purpose of the camera’s sensor?
to transmit optical light to electrical signal
How many fields are there in one frame of video?
two
How many lines per frame does the NTSC television format use?
525
Define the five basic switcher types:
Homing, Bridging, Looping, Alarming, Manual
What is the difference between a video monitor and a television?
A television has tuners; a monitor does not.
Should an aluminum foil-type coax be used for cctv?
Never
What are some advantages a DVR has versus an analog recorder?
Faster to review, better picture quality, more storage, password protection, less mati
Define the following multiplexers:
a. Simplex
b. Duplex
c. Triplex
a. Simplex: One at a time Record
b. Duplex: Two at a time Review
c. Triplex: Three at a time Live View
What determines the light gathering ability of the lens?
Diameter of the optics
What are the three most common types of flat panel monitors?
LCD, LED, Plasma
What are the colors used to generate an image on a CRT monitor?
Red, blue and green
What piece of equipment is used to display four cameras on a single monitor?
Quad splitter
How is a DVR different from an NVR?
DVR has limited capacity while the NVR (Network Remote Access) has a much larger capacity.
What is the difference between an analog matrix switch and a virtual matrix switch?
An analog matrix switch is when the components are switched by hand; the virtual is all on computer.
How does the day/night camera change to provide the best image for varying light conditions?
Use monochrome at night
What is the difference between a digital camera and an IP camera?
A digital camera is managed on a DVR and uses overcoax or UTP filter; the IP camera is managed over the network and on the Cat only)
What lens type is most like the human eye?
FFL - auto iris the answer depends on sensor size and viewfinder magnification, but the answer ends up being about 50mm for most full frame
Define one FtCd of illumination.
Amount of light viewed from one candle at one foot
Can you use a lens listed for use on a 1/4” sensor on a 1/2” sensor? Why or why not?
No - the picture would be smaller than the sensor
What lux level is considered to be a low light level?
Below .1075 lux
Define a virtual matrix switch
A router for cameras and monitors - computer based
What are some of the things that will affect the quality of a video image?
distance, wire methods, camera type, lens used, recording device, lighting
What is the difference between an analog camera and a digital camera?
An analog camera uses an electrical signal and film, while the digital camera converts image to data, which can be copied, shared, manipulated and stored, indefinitely, with zero image corruption.
The sensitivity of a camera is measured in what?
lux
What purpose do transmitters and receivers serve?
Transmitters balance the signal for transmission to an electrical signal.
Receivers unbalances the signal for display to a video signal.
